Minerals and some biochemical parameters determined from blood serum analyses in left displacement abomasum (LDA) affected and healthy dairy cows to evaluate the effect of displacement abomasum on mineral status, energy metabolism and liver function. Samples were collected from 60 affected cows and 60 healthy control cows matched with cases, based on herd, parity, and stage of lactation. Concen...

The objective of this study was to evaluate the influence of bull excretory products on the resumption of postpartum luteal function in primiparous, restricted-suckled cows. Hypotheses tested were that resumption of luteal function or proportions of cows that initiate luteal cycling did not differ among cows exposed to a bull (BE), exposed to excretory products of bulls (EPB), not exposed to a ...

In postpartum cows, ovulatory follicle size at time of insemination (GnRH/TAI) influenced pregnancy rates following TAI, but had no effect on pregnancy rates when cows spontaneously ovulated. Furthermore, cows that exhibited estrus (± 24 h of GnRH/TAI) had higher pregnancy rates compared to cows not in estrus. The objective was to assess the relationship between ovulatory follicle size and estr...

To investigate the effects of corn dried distillers grains plus solubles (DDGS) supplementation to cows fed corn stover and silage during late gestation, 27 multiparous beef cows (674 ± 17 kg; BCS, 5.6 ± 0.1) were divided randomly into 2 pens equipped with electronic feeders. For 10 wk, both groups were fed the basal diet for ad libitum intake while 1 group was supplemented (SUP; = 12) with DDG...

The objective of this study was to determine the effects of two different time of GnRH injection after artificial insemination (A.I) (d 6 and d 12) on reproductive performances of Holstein cows during the warm season.  Cows randomly assigned to treatments 1) No GnRH injection (control, n = 300),2) GnRH injection at day 6 after A.I (G6, n=300) and 3) GnRH injection at day 12 after A.I (G12, n=30...

OBJECTIVE To estimate seroprevalence of Mycobacterium avium subsp paratuberculosis (MAP) infection among adult dairy cows in Colorado and determine herd-level factors associated with the risk that individual cows would be seropositive. DESIGN Cross-sectional observational study. ANIMALS 10,280 adult (> or = 2 years old) dairy cows in 15 herds in Colorado. PROCEDURE Serum samples were test...

A total of 135 postpartum suckled zebu cows were assigned randomly at calving to two treatments: cows exposed to vasectomised bulls (Mature Bull Exposure, MBE) and cows not exposed to bulls (No Bull Exposure, NBE) for a period of 150 days postpartum. This study was conducted to determine the influence of bull biostimulation, season and parity on postpartum reproductive performance of Bos indicu...

Insulin responsiveness to glucose and tissue responsiveness to insulin, using the hyperglycemic clamp and the hyperinsulinemic euglycemic clamp techniques, were measured in lactating, late pregnant, and nonpregnant, nonlactating (NPNL) beef cows. The glucose infusion rate (GIR) in the hyperglycemic clamp technique was higher (P less than .05). in lactating cows than in NPNL cows. The plateau in...

The objective of this study was to determine the effects of two different time of GnRH injection after artificial insemination (A.I) (d 6 and d 12) on reproductive performances of Holstein cows during the warm season.  Cows randomly assigned to treatments 1) No GnRH injection (control, n = 300),2) GnRH injection at day 6 after A.I (G6, n=300) and 3) GnRH injection at day 12 after A.I (G12, n=30...

An experiment was conducted to investigate the effect of different types of ovarian cycles on reproductive indices and blood metabolites in 61 Holstein cows. Blood samples were taken from each cow between day 12 and day 50 postpartum (PP). Serum progesterone concentrations were measured to determine the onset of luteal function and different types of luteal dysfunctions in cows. Serum glucose, ...